# functions ------------------------------------------------------------------

def display_inventory(inv_type, chunky, skybar, valomilk, zagnut):
    print()
    print(inv_type.capitalize() + ' inventory')
    print('-----------------')
    print('{:8s} {:8d}'.format('Chunky', chunky))
    print('{:8s} {:8d}'.format('Skybar', skybar))
    print('{:8s} {:8d}'.format('Valomilk', valomilk))
    print('{:8s} {:8d}'.format('zagnut', zagnut))
    print('-----------------')

# main algorithm -------------------------------------------------------------

# -------------- read names of data files

initial_inventory = input('Name of file with the week\'s initial inventory: ')
transactions      = input('Name of file with the week\'s transactions     : ')
updated_inventory = input('Name of file with the week\'s updated inventory: ')

# -------------- read beginning inventory file

initial_inventory_file = open(initial_inventory, 'r')
for line in initial_inventory_file:
    bar,count = line.strip().lower().split()
    if bar == 'chunky':
        chunky = int(count)
    elif bar == 'skybar':
        skybar = int(count)
    elif bar == 'valomilk':
        valomilk = int(count)
    else: # bar == 'zagnut':
        zagnut = int(count)
initial_inventory_file.close()

# -------------- display beginning inventory

display_inventory('Initial', chunky, skybar, valomilk, zagnut)

# -------------- process week's transactions

change_in_chunky   = 0
change_in_skybar   = 0
change_in_valomilk = 0
change_in_zagnut   = 0
total_sales        = 0
total_purchases    = 0


transaction_file = open(transactions, 'r')
for line in transaction_file:
    tran_type, bar, count = line.strip().split()
    tran_type = tran_type.lower()
    bar = bar.lower()
    count = int(count)
    
    if tran_type == 'sale':
        total_sales += 1
        count = -count
    else:
        total_purchases += 1
    
    if bar == 'chunky':
        change_in_chunky += count
    elif bar == 'skybar':
        change_in_skybar += count
    elif bar == 'valomilk':
        change_in_valomilk += count
    else: # bar == 'zagnut':
        change_in_zagnut += count

transaction_file.close()

# -------------- display the number of  transactions processed

print()
print('Total sales     :', total_sales)
print('Total purchases :', total_purchases)

# -------------- update inventory

chunky   += change_in_chunky
skybar   += change_in_skybar
valomilk += change_in_valomilk
zagnut   += change_in_zagnut

# -------------- display ending inventory

display_inventory('Closing', chunky, skybar, valomilk, zagnut)

# -------------- write ending inventory file

ending_inventory_file = open(updated_inventory, 'w')
print('chunky',   chunky,   file=ending_inventory_file)
print('skybar',   skybar,   file=ending_inventory_file)
print('valomilk', valomilk, file=ending_inventory_file)
print('zagnut',   zagnut,   file=ending_inventory_file)
ending_inventory_file.close()